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[amigo]

Okay, here is my application:
I like to use VT7300 LON model to control a fancoil that has 2 position heating and cooling valves, 3-speed fan and a modulating economizer.
VT7300 as far as I can tell does not have an economizer output option, that is okay. Let's say I have another LON programmable controller that can control the economizer.
My problem is when I am in economizer mode how do I tell VT7300 to still keep using fan speed control (low to high) based on demand but not use its cooling output? Obviously this is when fan speed control is at Auto.
I do not want to use NviFanSpeedCmd because if user has set speed control to low using keypad (for noise consideration) then I am overriding that condition.

I have multiple fancoils with this challenge.

Thanks.

[Zinc22]

You may have more than one option depending on what type of installation this will be used on.

If these are large commercial FCU's you may want to try our model that has on board economizer control.
VT7605B1000E. It features a modulating dry bulb economizer control. However, please note the following
- User interface is closer to a traditional heat cool thermostat
- Single fan speed only
- N.C. valves only

Or if you are using a 3rd party economizer control, you may just feed the cooling demand from the thermostat to that 3rd party device and also let it control the cooling valve.

See below and let me know if this helped.